If I understand you properly, you appear to be asking what the best dialplan design is within UCM for dialing between on-net sites. This answer has a whole chapter dedicated to it in the UCM SRND; however, if I make a long list of assumptions about your environment:
Baring number overlap scenarios, each user's DN typically exists in a single partition such as Enterprise_PT.
When user A calls user B's extension the device-level CSS of user A includes the single Enterprise_PT. No translation is needed.
IF you have numbering overlap and need to use inter-site access codes (also explained in the SRND), then the DNs are configured in their fully qualified form and a single per-site translation pattern exists to expand intra-site abbreviated dialing to the full form. Example: 85551234 is the DN configured in UCM. Users are taught that 8 is the inter-site access code, 555 is the site code for site B, and 1234 is the user's four-digit extension at site B. Others at site B would dial 1234 and UCM would translate the intra-site call into 85551234.
SIP traces provide key information in troubleshooting SIP Trunks, SIP
endpoints and other SIP related issues. Even though these traces are in
clear text, these texts can be gibberish unless you understand fully
what they mean. This document attempts to br...
Please find the attached HTML document, download and open it on your PC.
This provides an easy to use form where you simply answer a few
questions and it will render the proper jabber-config.xml file for you
to copy/paste. There is built in logic to verif...
CUCM Database Replication is an area in which Cisco customers and
partners have asked for more in-depth training in being able to properly
assess a replication problem and potentially resolve an issue without
involving TAC. This document discusses the bas...